Vacuum cooling apparatus



Dec. 13, 1960 F. J. H1BBs,JR

VACUUM COOLINGv APPARATUS 6 Sheets-Sheet 1 Filed Oct. 2l. 1957 INV ENTOR. FRAN/(J H/Bs, JR.

A TTORNEVS lBY L m Dec. 13, 1960 F. J. HIBBs, JR

VACUUM COOLING APPARATUS 6 Sheets-Sheet 2 Filed Oct. 2l. 1957 N ASMINVENTOR. FRAN/f J H/Bs, JR.

ATTORNEYS Dec. 13, 1960 F. J. HlBBs, JR

VACUUM COOLING APPARATUS 6 Sheets-Sme?l 3 Filed Oct. 21. 1957 FRANK J,Lf/Beim 3%@ mf f/f mm; c

A TTORNEVS `Dec. 13', 1960 F. J. HIBBS, JR

VACUUM COOLING APPARATUS Filed 001:. 21. 1957 6 Sheets-Sheet 4 INVENTOR.FRA/VK J H/BB5,JR.

' BWMMUJ AT TORNEVS Dec. 13, 1960 F. J. HIBBS, JR 2,963,876

VACUUM COOLING APPARATUS vFiled Oct. 2l, 1957 6 Sheets-Sheet 5 INVENI'OR. FRAN/f J H/s, JR. 1

BWM/M A TTOPNEVS Dec. 13, 1960 F. J. HIBBS, JR 2,963,876

VACUUM COOLING APPARATUS Filed oct. 21,1957 e sheets-sheet e IN V ENTOR. FRA NK J. H/s, JR.

ivf/76 Aff/142 A T rom/5 ys tUnited rates Patent 2,963,876 VACUUMCOOLING APPARATUS Frank J. Hibbs, Jr., Inglewood, Calif., assignor toAssoelated Refrigerating Engineers, a corporation Filed Oct. 21, 1957,Ser. No. 691,212 4 Claims. (Cl. 62-173) My invention relates to meanslargely used for the cooling of produce as it is removed from the eldsand prior to shipment. Devices of this sort have come into widespreaduse in various agricultural areas within the last few years. In thepresent instance it is primarily an object of the invention to providean eiective unit of substantial size yet one which is portable or atleast semiportable in order that it can be moved from one area toanother as various crops are available trom time to time.

Another object of the invention is to provide such an apparatus which issubstantially self contained so that it can be utilized in variousdifferent locations or environments and without the necessity of havingpublic power or the like immediately available.

A still further object of the invention is to provide a coolingapparatus eilective to operate over a relatively wide range of capacity.

Another object of the invention is to provide an apparatus of the sortindicated which is thermally economical and which can be operated forindefinite periods virtually on a self contained basis.

A still further object of the invention is to provide a vacuum coolingapparatus in which water ice, originally in block form, is utilized as aheat absorber.

A still further object of the invention is in general to provide animproved vacuum cooling apparatus.

Other objects, together with the foregoing, are attained in theembodiment of the apparatus described in the accompanying descriptionand disclosed in the accompanying drawings in which:

Figure 1 is a plan of a vacuum cooling apparatus constructed inaccordance with the invention.

Figure 2 is a cross-section the planes of which are indicated by theline 2-2 of Figure 1.

Figure 3 is a cross-section the plane of which is indicated by the line3 3 of Figure l and with part of the structure broken away.

Figure 4 is a cross-section of the structure, the plane of section beingindicated by the line 4 4 of Figure l.

Figure 5 is a cross-section to an enlarged scale, the plane of sectionbeing indicated by the line 5-5 of Figure 1.

Figure 6 is a cross-section to an enlarged scale, the plane of sectionbeing indicated by the line 6--6 of Figure l.

Figure 7 is a detail in cross-section, the plane of section beingindicated by the line 7 7 of Figure 1.

Figure 8 is a diagrammatic showing of the structure with particularreference to the piping.

While the vacuum cooling apparatus of the invention can be embodied in anumber of dierent forms and configurations to t it for especiallydefined services, it has been successfully incorporated on a commercialscale substantially as shown herein.

In this form of device there is provided a vacuum chamber 6, sometimesreferred to as a produce chamber, which is an elongated,circular-cylindrical tube resting on or close to the ground. The tube isprovided interiorly with accommodations for trucks or pallets holdingthe produce to be cooled and is likewise provided at one or both endswith a door 7 or other means for ingress or egress. The chamber 6 iscapable of withstanding atmospheric pressure under a relatively highvacuum and when closed is air tight. The vacuum chamfsfice ber 6 isusually of a size so that it can by itself be hauled by highwaytransport when disconnected from the remaining structure.

In the usual arrangement there is provided also a cooling chamber or icechamber 8. his is of circularcylindrical configuration, is parallel tothe chamber 6 and is likewise disposed on or near the ground. Thechamber S by itselt` is transportable by highway equipment. lnteriorlyit is provided with a rack 9 to support ice blocks 11 supplied throughhatches 12. The chamber S is air tight and is connected to the chamber 6by means of a pair of air conduits 13 and 14 so that the interior of thechamber 6 is in communication with the interior f the chamber 8. In theusual practice an ice truck periodically furnishes ice through thehatches 12 in between cycles of evacuation of the chambers 6 and 8.`

Air and moisture from the interior of the chamber 6 are drawn throughthe conduits 13 and 14 -to lthe interior of the ice chamber 8 and overthe ice therein. This is accomplished by a mechanically driven, positivedisplacement vacuum pump 16. The pump includes a irst stage 17 and asecond stage 13 mechanically connected by a drive shaft 19 and bothdriven through a belt 21 by an internal combustion engine 22 having aradiator 23 thereon. For simplicity some of the various pump connectionsand interconnections are not shown. 1t is sulicient to state generallythat a duct 26 (Figures 2 and 8) connects the interior of the icechamber 8 to the vacuum pump 16, preferably through a filter 27. Thepump 16 discharges to the atmosphere and is e'ective when operating toevacuate the chamber 6 and the chamber 8 to the desired extent. Duringthis evacuation process the warm air and moisture withdrawn from thevacuum chamber 6 are cooled and partly condensed by passing over the iceblocks 11. The ice blocks, upon the absorption of the heat, melt andprovide a supply of ice water which, with the condensed moisture,trickles down and rests in the bottom of the tube 8.

As often as is neccessary and between cycles of vacuum operation (whichnormally are from twenty minutes to a half hour in duration) when theapparatus is at atmospheric pressure, an ice water drain line 31(Figures l, 4 and 8) is opened by manipulation of a valve 32 so that theice water from the ice chamber 8 drains by gravity into an ice watersump 33. At the conclusion of the draining operation and when thechambers are again to be evacuated, the valve 32 is again closed. The owof ice Water into the ice water sump 33 is intermittent.

The ice water, instead of being entirely wasted, is collected forfurther uses. Since customarily the amount of ice melted is in excess ofrequirements for further heat absorption, the ice Water sump tank 33 isprovided with an overflow Weir 34 so that any level in excess of thatindicated by the line 36 in Figure 6 overflows into an outlet 37 towaste.

Ice water from the sump tank 33 destined for further use is pumped intoa cooling tank 41. This is accomplished by a centrifugal pump 42 havingan inlet pipe 43 extending into the sump tank 33 and being suitablydriven by an electric motor 44. The motor is included in an electriccircuit (not shown) and is controlled ny a switch 46 actuated by a oatrod 47 connected to a oat within a screened housing 4S in the tank 33.When the ice water in the sump tank 33 rises, the motor 44 is energized.Ice water is withdrawn through the inlet 43 and through the pump 42 todischarge through a pipe 49 into the upper portion of the cooling tank41. If the pump 42 is not able to keep the level of ice water lowenough, then overliow occurs as described. In the event the level isadequately lowered, the oat 48 in sinking opens the switch 46 anddeenergizes the motor 44. The

kto the exothermic unit. .mits its impulse or signal through a line 84to a concentrifugal pump 51 (Figures 1 and 7) operated by an velectricmotor 52. The pump 51 receives a supply of ice water through an inlet 53connected to the bottom portion (Figures 7 and 8) of the cooling tank41. The pump V51 discharges through a conduit 54 (Figures 6, 7 and 8)which leads through a T 56 (Figure 6) into a pipe 57 .extending throughthe tank 41 (Figure l) for a portion of its length and having branches(Figure l) 58 and S9 extending to the two stages of the vacuum pump 16.If desired, the line 57 may also have a branch 61 extending to theradiator 23 of the engine 22. Since the apparatus Vis divided intoseparately portable units, the pipe line 57,

at some convenient point in its length, is interrupted by a lflexibleremovable hose 62.

The vacuum vpump 16 and the engine 22 are normally provided with jackets63 and 64 for water cooling.

Water received in the jackets, even though it is ice water, is heated byabsorption of heat from the exothermic units such as the vacuum pump 16and the engine 22 and is then returned to the cooling tank 41 bysuitable branches 66 and 67 leading into a return line 68. A hosesection 69 therein is connected with a return pipe 71 (Figure 1) whichpasses around much of the inside of the cooling tank 41 and emerges in asection 72 (Figure 6).

From the section 72 the returning warm water has alternate pathsgoverned in accordance with a temperature regulating mechanism. A threeway valve 73'is appropriately situated on the side of the cooling tank41 and has one branch 74 connected to the warm water return line 72. Thevalve has another branch 76 connected to an overflow conduit 77 leadingto a convenient point 78 for the discharge of any overflow released bythe valve 73. Another branch 79 of the valve 73 leads downward-,preferably of a standard sort operated bycompressed air derived from asource (not shown) through a pipe line 82. A thermometer bulb 83 in theT 56 ris responsive to the temperature of the'water. owiug outwardlythrough thepipe 54 and into the supply pipe 57 going The thermostaticbulb 83 transtrol Vvalve 86. This has the property of regulating the`ilow of air through the line 82 to the valve 81'exactly in accordancewith the temperature of the'thermostatic bulb 83. Thus, the valve 73 ispositioned in such a Way as to mix or divert the warm waterreturning-through the conduit 72. The effect of this mixtureor diversionis to provide in the pipe l54 a mixture of ice waterY and warmed waterreturning to the exothermic devices. temperature of .the returning orcooling water is thus maintained at substantially a set, optimum value.

In the event there is excessive warm Water, it is Adiverted through theoverflow 78 to Waste, whereas if the 4thermostatic bulb 83 so requires,much or allrof the-returned, warmed water is again fed through the pump51 to be recirculated to the vacuum pump 16 and, if conto a temperatureeffective upon `the thermostaticlbulb 83 "and the valve 73. Above thattemperature there is an increasing admixture of ice water so that whenthe mech- The.

anism has gotten hot and requires greater cooling greater amounts of icewater are used for that purpose.

Pursuant to the inventions` there is provided a vacuum cooling apparatuswhich is substantially self-contained since no supply ofkcoolng waterforVthe yacuum pump and for the internal combustion engine isnecessaryuother than that provided by the melted ice. Sincerthe internalcombustion engine provides the necessary power for the apparatus it canbeoperated in any remote area. The ice blocks are trucked inperiodically and fuel for the engine is likewise trucked in.Furthermore, the apparatus when Vdismantled can readily be trucked to anew location and there set up and operated under widely variantconditions of load, that is light load, or heavy load, and under widelyvariant ambient temperature conditions. A greatly improved apparatus isthus aorded.

What is claimed is: Y

1. A vacuum cooling apparatus comprising a vacuum chamber, a vacuum pumpconnected to said chamber for reducingV the pressure therein, a waterjacket on said pump, a cooling water tank, an ice chamber connectedbetween said vacuum chamber and said vacuum pump, means for transferringice water from said ice chamber to said Water tank, means for supplyingwater from said tank to said jacket, means for returning water from saidjacket to said tank, and means responsive to temperature of water insaid supplying means for mixing therewith water from said returningmeans.

2. A vacuum cooling apparatus comprising a vacuum chamber, an icechamber, a water cooled vacuum pump, means for connecting said pump tosaid chambers for drawing air from said vacuum chamber through said icechamber whereby said ice melts to form ice water, a cooling tank, meansfor transferring said ice water to said cooling tank, means forsupplying said vacuum pump with cooling water, means for furnishing saidsupplying means with ice water from said cooling tank and with coolingwater returned from said vacuum pump, and means responsive totemperature of the water owing in said supplying means for proportioningsaid ice water Vand said cooling water furnished said supplying means.

3. A vacuum cooling apparatus comprising a vacuum chamber, an icechamber, an air conduit connecting said chambers, a water cooled vacuumpump, a duct connecting said ice chamber and said vacuum pump, a sumptank, means for conducting ice water from said ice chamber to said sumptank, a cooling tank, means for transferring ice water from said sumptank to said cooling tank, a water pump, means for connecting saidcooling tank and the inlet of said water pump, a pipe connecting theoutlet of said water pump to the cooling mechanism of said vacuum pump,a conduit joining the cooling mechanism of said vacuum pump to said con--necting means, an overowline, a valve in said conduit and joined tosaid overow line, and means responsive to temperature in said pipe foroperating said valve to divert ow in said conduit into said overow line.

4. A vacuum cooling apparatus comprising a Vacuum chamber adapted tohave moisture therein, a vacuum pump connected to withdraw air andmoisture from said vacuum chamber, means for passing said air andmoisture over ice resulting in a supply of cold water including meltedice and said moisture, means utilizing heat from said vacuum pump forheating said cold water, and means for recirculating some of said heatedwater through said utilizing means.

References Cited in the le of this patent UNITED STATES PATENTS

